The document describes the order and key characteristics of 29 orders of insects. It discusses their physical features such as number of wings, antennae, mouthparts, eyes and other distinguishing anatomical traits. The orders covered include Thysanura, Diplura, Protura, Collembola, Ephemeroptera, Odonata, Plecoptera, Grylloblattodea, Orthoptera, Phasmida, Dermaptera, Embioptera, Dictyoptera, Isoptera, Zoraptera, Psocoptera, Mallophaga, Siphonculata, Hemiptera, Thysanoptera, Neuroptera, Cole

1. ORDER OF INSECTS
H.Kalimani
II M.Sc Zoology
Hajee Karutha Rowther Howdia College
Uthamapalayam

2. 1.THYSANURA
 Primitively wingless
 3 terminal filaments, roughly equal in length including 2 cerci and a median
caudal filament
 Eyes small or missing
 Body flat, often covered with dusty scales
Firebrat Silverfish

3. 2.DIPLURA
 Narrow, elongate body, usually colourless
 Moniliform antennae
 Eyes absent
 2 abdominal cerci sometimes in the form of darker coloured pincers
Compodea staphylinus

4. 3.PROTURA
 Elongate, cylindrical body, small styli present first 3 segment of abdomen
 Eyes absent, wingless
 Cerci and abdominal filaments entirely absent
 Antennae absent, cone-shaped head
 Body unpigmented usually white or ivory in color
Proturan

5. 4.COLLEMBOLA
 Either elongate and cylindrical or more compact and spherical
 Simple eyes consisting upto 8 ocelli
 Moniliform antennae mostly 6 segments
 Mouthparts hidden byoral folds or cheeks
 Forked tail-like (furca) organ underside of the abdomen, collophore tube-
like structure on ventral side of first abdominal segment
 Soft bodied covered with scales
Springtail Snow flea

6. 5.EPHEMEROPTERA
 2 pair of membranous Triangular wings, hindwings smaller
 2 or 3 long abdominal filaments
 Short, bristle-like antennae
Mayfly

7. 6.ODONATA
 Abdomen long and slender
 Large compound eyes, 3 ocelli
 Very small bristle-like antennae
 Mandibulate mouthparts
 2 pairs of membranous wings of similar shape and size
 Complex wing venation with many cells
Dragonfly Damselfly

8. 7.PLECOPTERA
 Elongated, flattened, soft body
 2 pairs of wings that are held curved around the body at rest. Some species
are wingless while others have reduced wings
 Hind wings slightly wider than forewings
 Long leg, mandibulate mouthparts
 2 cerci at tip of abdomen, long antennae
Stonefly

9. 8.GRYLLOBLATTODEA
 Body cylindrical, wingless
 Mouthparts mandibulate, hypognathous, antennae slender filiform
 5 segmented tarsi
 Cerci long, 8 segmented
Grylloblatta (Ice crawler)

10. 9.ORTHOPTERA
 2 pair of wings, forewing narrower, hind wing membranous
 Large compound eyes, mandibulate mouthparts
 Antennae may be short t very long depending on species, grasshopper have
short antennae while crickets and katydids generally long antennae
 Hind legs are enlarged and modified for jumping
Cricket Grasshopper Katydid

11. 10.PHASMIDA
 Body shape variable but most resemble sticks, leaves or grass
 Prothorax shorter than meso or metathorax
 2 pairs of wings although some species wingless, short wing when present
consist hardened forewings, larger membranous hind wings
 Antennae filiform, may be either long or short
Stick insect Leaf insect

12. 11.DERMAPTERA
 Flattened elongated body
 Heavily sclerotised pincer-like cerci
 2 pairs of wings, forewings short and hardened, hind wing membranous,
some species wingless
 Moderately long antennae
 Chewing mouthparts
Earwigs

13. 12.EMBIOPTERA
 Elongated, cylindrical body
 Enlarged front tarsi contains silk glands used to create galleries theylive in
 Short legs
 2 pairs of membranous wings in some male species. All females are
wingless
 2 short cerci, which in male web-spinners are unequal in size and shape
Webspinner
Female Male

14. 13.DICTYOPTERA
• Large or medium sized insects
• They can separated into 2 suborders Blattodea and Mantodea
• 2 pairs of wings but the front pair is leathery
• Antennae are longer
• Cerci are visible and the hairs on cercus are very sensitive
• Nocturnal and omnivorous
Cockroach Mantids

15. 14.ISOPTERA
 Pale, elongate soft body
 Social insects with different castes
 2 pairs of membranous wings of equal length. Wings are present in
reproductive castes only and shed after mating
 Antennae about the same length as the head
 Chewing mouthparts, pincer like mandibles
Termites

16. 15.ZORAPTERA
 Small, soft bodied
 Wings often absent with reduced venation when present
 Tarsi 2 segmented, Cerci 1 segmented,
 Moniliform Antennae 9 segmented
 Mouthparts chewing
Zorapteran

17. 16.PSOCOPTERA
 Soft bodies, long antennae
 Large head with protruding eyes
 2 pairs of membranous wing, reduced venation, forewing larger than
hindwings, some species wingless
Barklice Booklice

18. 17.MALLOPHAGA
 Small, wingless, dorsoventrally flattened
 Chewing mouthparts
 Small compound eyes, no ocelli, some eyeless
 Claws well developed for clinging to the host
 All ectoparasites found in birds
Bird lice

19. 18.SIPHUNCULATA
 Small, wingless, parasitic
 Piercing/Sucking mouthparts,
 Short antennae
 Single claw on each tarsus
 Small often non functioning eyes
Body lice Head lice

20. 19.HEMIPTERA
 2 pairs of wings, some species wingless, other have only forewings, wings
are membranous but in some species may hardened at the base
 Piercing or sucking mouthparts, appearing at sharply pointed tube knoen as
proboscis or rostrum
 Compound eyes of various forms, upto 3 ocelli present
 Antennae vary may be either short or long and conpicuous
Aphids Cicadas

21. 20.THYSONOPTERA
 Antennae short 6-10 segments
 Head narrow forming anteriorly a conical mouth opening
 Body cylindrical or spindle-shaped
 Front and hind wings slender, rod like with dense fringe of long hairs, may
species wingless
 Tarsi 1-2 segmented
Thrips

22. 21.NEUROPTERA
 Elongate, soft body
 2 pairs of membranous wings of relatively equal size, Complex wing
venation with main forked along the bottom edge of the wing
 Mandibulate mouthparts
 Relatively large compound eyes
 Often long filiform antennae, clubbed in some species
Antlion Lacewing

23. 22.COLEOPTERA
 2 pairs of wings. Forewings hardened, hind wings membranous
 Mandibulate mouthparts designed for biting and chewing
 Antennae present in variety of forms
 Compound in a variety of sizes and shape
Beetles Weevils

24. 23.STREPSIPTERA
 Males with fan-shaped hind wings and club-shaped front wings, female
wingless
 Compound eyes resemble raspberies
 Antennae often branched
Stylops

25. 24.MECOPTERA
 2 pairs of membranous wings almost equal size, some species wingless
 Mandibulate mouthparts at the end of a bead like projection on the head
 Very long spindly leg with strong claws
 Long filiform antennae
 Well developed compound eyes
Scorpionfly

26. 25.SIPHONOPTERA
 Laterally compressed body
 Piercing sucking mouthparts
 Enlarged hind legs adapted for jumping
 Strong tarsal claws adapted for holding onto their hosts
 Backward pointing hairs and bristles for ease for movement through the
hair of a host
 Small antennae which tuck away into special groves in the head
Flea

27. 26.DIPTERA
 One pair of membranous wings, hind wings reduced to small club like
structures called halters
 Sucking mouthparts, sometimes piercing
 Large compound eyes
 Short simple antennae, frilled or bushy in mosquito and craneflies
Mosquito Green bottle fly

28. 27.LEPIDOPTERA
 2 pairs of membranous wings that covered in tiny scales, few moths are
wingless
 Large compound eyes, one ocelli present above each eye
 Antennae present, antennae long and slender in female moths and generally
feathery in male moths. Butterflies have clubbed antennae
 Mouthparts are formed into a sucking tube knowm as haustellum
Moth Butterfly

29. 28.TRICHOPTERA
 Elongate body
 2 pairs of membranous wings that are differ in size, wings covered in fine
hairs
 Reduced mouthparts
 Long tapering, filiform antennae
Caddiesfly

30. 29.HYMENOPTERA
 2 pairs of membranous wings, some may wingless
 The forewings are larger than hind wings and held together by small
hooks(hamuli)
 Female have hardened ovipositor which may modified for sawing, piercing,
stinging
 Wasp waist present in first two segment of ants, bees, wasps
 Chewing mandibulate mouthparts, bees lower lip modified to form tongue
 Large compound eyes
Cuckoo wasp Bee Ant